Sperm sample morphology is not correlated with ICSI outcomes

Abstract

OBJECTIVE: Intracytoplasmic sperm injection (ICSI) has become the treatment of choice of severe male factor of infertility. The role of the spermatozoa in the success of ICSI is controversial. We hypothesized that the sperm sample morphology is correlated to the quality of the single sperm used for ICSI, therefore the aim of the present study was to investigate whether embryo quality is influenced by the sample morphology in ICSI cycles and to compare sperm morphology pre and post-swim-up. MATERIAL AND METHODS: Ninety assisted reproduction cycles were performed between August 2004 and March 2005. All semen samples were obtained by masturbation and processed by swim up. Before swim-up, routine semen analysis was performed and such before as after sperm preparation, morphology was assessed by Kruger strict criteria. The women were submitted to controlled ovarian hyperstimulation achieved by a long pituitary down regulation using a GnRH agonist followed by ovarian stimulation with recombinant-FSH. Third six hours before ovum pick-up rhCG was administrated to trigger ovulation. After ICSI, 535 embryos were assessed for normal fertilization, pro-nuclei morphology, early cleavage and morphology and number of cells on the second and third day of development (day transfer). Correlation between percentage of normal sperm morphology (pre and post-swim-up) and ICSI outcomes were analyzed. RESULTS: Our results didn't show any significant correlation between the percentage of normal sperm morphology on the whole sample, neither before nor after swim-up, and the ICSI outcomes parameters evaluated, such as normal fertilization rate (P=0,602 and P=0,894 for pre and post swim-up respectively); pro-nuclei morphology (P=0,289 and P=0,316 pre and post swim-up respectively); early cleavage evaluation (P=0,224 and P=0,604 pre and post swim-up respectively) and embryo morphology in the third day of development (P=0,113 and P=0,807 pre and post swim-up respectively). CONCLUSIONS: Our findings demonstrated that there are no correlations between morphological assessment of the semen sample and ICSI outcomes. Indeed, the embryologist selects the spermatozoa with better morphology and motility for ICSI. Therefore, we concluded that morphology in human spermatozoa sample according to Kruger's criteria has no predict value for ICSI outcomes.